In general, a lighting apparatus using light emitting diodes (LEDs), in which the LEDs that generate light are arranged in one surface of a base and a spherical globe is provided to cover the LEDs, diffuses and transfers light from the LEDs to an outside. Such a lighting apparatus transfers heat from the LEDs to the base and transfers the heat to the outside from another surface (heat transfer surface) of the base, which is held in contact with the ambient air.
It is desirable that the lighting apparatus using the LEDs have total luminous flux (measure indicating brightness of light emitted by LEDs) that is approximately equal to that of a lighting apparatus (incandescent bulb or the like) using a typical filament or the like.
In order to increase the total luminous flux, it is necessary to use LEDs having higher luminance, which correspondingly increases an amount of heat generation of the LEDs. The heat generated by the LEDs influences elements of the LEDs themselves, a circuit board such as a power circuit, and the like, so that the performance of the elements of the LEDs, the circuit board, and the like is deteriorated. Therefore, in order to enhance heat transfer performance of the lighting apparatus, it is necessary to increase a surface area of a heat transfer surface of the base.
Therefore, in order to enhance the heat transfer performance, it is necessary to increase the size of the lighting apparatus.
A lighting apparatus having an enhanced heat transfer performance without increasing the size of the lighting apparatus is provided.
A lighting apparatus according to an embodiment includes: a light source that emits light; a hollow heat-transfer member including an outer surface on which the light source is disposed; and a light guiding member that covers the light source and at least part of the outer surface along the outer surface.